BREAKING Overlay transaction support.

.gitlab-ci.yml

@@ -113,9 +113,12 @@ cargo-check-benches:
   <<:                              *docker-env
   script:
     - BUILD_DUMMY_WASM_BINARY=1 time cargo +nightly check --benches --all
+    - cd ./primitives/state-machine/fuzz
+    - time cargo check
     - sccache -s
 
 
+
 cargo-check-subkey:
   stage:                           test
   <<:                              *docker-env

client/src/client.rs

@@ -1175,7 +1175,7 @@ impl<B, E, Block, RA> Client<B, E, Block, RA> where
 				.trigger(
 					&notify_import.hash,
 					storage_changes.0.into_iter(),
-					storage_changes.1.into_iter().map(|(sk, v)| (sk, v.into_iter())),
+					storage_changes.1.into_iter().map(|(storage_key, v)| (storage_key, v.into_iter())),
 				);
 		}
 

frame/contracts/src/wasm/runtime.rs

@@ -647,7 +647,7 @@ define_env!(Env, <E: Ext>,
 	// Record a request to restore the caller contract to the specified contract.
 	//
 	// At the finalization stage, i.e. when all changes from the extrinsic that invoked this
-	// contract are commited, this function will compute a tombstone hash from the caller's
+	// contract are committed, this function will compute a tombstone hash from the caller's
 	// storage and the given code hash and if the hash matches the hash found in the tombstone at
 	// the specified address - kill the caller contract and restore the destination contract and set
 	// the specified `rent_allowance`. All caller's funds are transfered to the destination.

frame/support/src/storage/mod.rs

@@ -26,6 +26,21 @@ pub mod child;
 #[doc(hidden)]
 pub mod generator;
 
+/// Execute under a new transactional layer.
+///
+/// If the result of execution is an error,
+/// the transactional layer get reverted; otherwise
+/// it is committed.
+pub fn with_transaction<R, E>(f: impl FnOnce() -> Result<R, E>) -> Result<R, E> {
+	sp_io::transaction::start_transaction();
+	let result = f();
+	match result {
+		Ok(_) => sp_io::transaction::commit_transaction(),
+		Err(_) => sp_io::transaction::discard_transaction(),
+	}
+	result
+}
+
 /// A trait for working with macro-generated storage values under the substrate storage API.
 ///
 /// Details on implementation can be found at

primitives/api/test/tests/runtime_calls.rs

@@ -104,7 +104,6 @@ fn calling_with_both_strategy_and_fail_on_native_should_work() {
 	assert_eq!(runtime_api.fail_on_native(&block_id).unwrap(), 1);
 }
 
-
 #[test]
 fn calling_with_native_else_wasm_and_fail_on_wasm_should_work() {
 	let client = TestClientBuilder::new().set_execution_strategy(ExecutionStrategy::NativeElseWasm).build();

primitives/externalities/src/lib.rs

@@ -37,16 +37,16 @@ mod scope_limited;
 /// Provides access to the storage and to other registered extensions.
 pub trait Externalities: ExtensionStore {
 	/// Read runtime storage.
-	fn storage(&self, key: &[u8]) -> Option<Vec<u8>>;
+	fn storage(&mut self, key: &[u8]) -> Option<Vec<u8>>;
 
 	/// Get storage value hash. This may be optimized for large values.
-	fn storage_hash(&self, key: &[u8]) -> Option<Vec<u8>>;
+	fn storage_hash(&mut self, key: &[u8]) -> Option<Vec<u8>>;
 
 	/// Get child storage value hash. This may be optimized for large values.
 	///
 	/// Returns an `Option` that holds the SCALE encoded hash.
 	fn child_storage_hash(
-		&self,
+		&mut self,
 		storage_key: ChildStorageKey,
 		child_info: ChildInfo,
 		key: &[u8],
@@ -76,7 +76,7 @@ pub trait Externalities: ExtensionStore {
 	///
 	/// Returns an `Option` that holds the SCALE encoded hash.
 	fn original_child_storage_hash(
-		&self,
+		&mut self,
 		storage_key: ChildStorageKey,
 		child_info: ChildInfo,
 		key: &[u8],
@@ -86,7 +86,7 @@ pub trait Externalities: ExtensionStore {
 	///
 	/// Returns an `Option` that holds the SCALE encoded hash.
 	fn child_storage(
-		&self,
+		&mut self,
 		storage_key: ChildStorageKey,
 		child_info: ChildInfo,
 		key: &[u8],
@@ -124,13 +124,13 @@ pub trait Externalities: ExtensionStore {
 	}
 
 	/// Whether a storage entry exists.
-	fn exists_storage(&self, key: &[u8]) -> bool {
+	fn exists_storage(&mut self, key: &[u8]) -> bool {
 		self.storage(key).is_some()
 	}
 
 	/// Whether a child storage entry exists.
 	fn exists_child_storage(
-		&self,
+		&mut self,
 		storage_key: ChildStorageKey,
 		child_info: ChildInfo,
 		key: &[u8],
@@ -139,11 +139,11 @@ pub trait Externalities: ExtensionStore {
 	}
 
 	/// Returns the key immediately following the given key, if it exists.
-	fn next_storage_key(&self, key: &[u8]) -> Option<Vec<u8>>;
+	fn next_storage_key(&mut self, key: &[u8]) -> Option<Vec<u8>>;
 
 	/// Returns the key immediately following the given key, if it exists, in child storage.
 	fn next_child_storage_key(
-		&self,
+		&mut self,
 		storage_key: ChildStorageKey,
 		child_info: ChildInfo,
 		key: &[u8],
@@ -202,6 +202,19 @@ pub trait Externalities: ExtensionStore {
 	///
 	/// Returns the SCALE encoded hash.
 	fn storage_changes_root(&mut self, parent: &[u8]) -> Result<Option<Vec<u8>>, ()>;
+
+	/// Start a new transactional layer.
+	fn storage_start_transaction(&mut self);
+
+	/// Discard current transactional layer, pending changes of this transaction layer are
+	/// dropped.
+	/// The transactional layer is closed, a new one is started if this was the last layer.
+	fn storage_discard_transaction(&mut self);
+
+	/// Commit current transactional layer.
+	/// The changes stay attached to parent transaction layer and could still be discarded.
+	/// The transactional layer is closed, a new one is started if this was the last layer.
+	fn storage_commit_transaction(&mut self);
 }
 
 /// Extension for the [`Externalities`] trait.

primitives/io/src/lib.rs

@@ -86,7 +86,7 @@ fn child_storage_key_or_panic(storage_key: &[u8]) -> ChildStorageKey {
 #[runtime_interface]
 pub trait Storage {
 	/// Returns the data for `key` in the storage or `None` if the key can not be found.
-	fn get(&self, key: &[u8]) -> Option<Vec<u8>> {
+	fn get(&mut self, key: &[u8]) -> Option<Vec<u8>> {
 		self.storage(key).map(|s| s.to_vec())
 	}
 
@@ -102,7 +102,7 @@ pub trait Storage {
 	/// This function specifically returns the data for `key` in the child storage or `None`
 	/// if the key can not be found.
 	fn child_get(
-		&self,
+		&mut self,
 		child_storage_key: &[u8],
 		child_definition: &[u8],
 		child_type: u32,
@@ -119,7 +119,7 @@ pub trait Storage {
 	/// doesn't exist at all.
 	/// If `value_out` length is smaller than the returned length, only `value_out` length bytes
 	/// are copied into `value_out`.
-	fn read(&self, key: &[u8], value_out: &mut [u8], value_offset: u32) -> Option<u32> {
+	fn read(&mut self, key: &[u8], value_out: &mut [u8], value_offset: u32) -> Option<u32> {
 		self.storage(key).map(|value| {
 			let value_offset = value_offset as usize;
 			let data = &value[value_offset.min(value.len())..];
@@ -137,7 +137,7 @@ pub trait Storage {
 	///
 	/// See `child_get` for common child api parameters.
 	fn child_read(
-		&self,
+		&mut self,
 		child_storage_key: &[u8],
 		child_definition: &[u8],
 		child_type: u32,
@@ -217,15 +217,15 @@ pub trait Storage {
 	}
 
 	/// Check whether the given `key` exists in storage.
-	fn exists(&self, key: &[u8]) -> bool {
+	fn exists(&mut self, key: &[u8]) -> bool {
 		self.exists_storage(key)
 	}
 
 	/// Check whether the given `key` exists in storage.
 	///
 	/// See `child_get` for common child api parameters.
 	fn child_exists(
-		&self,
+		&mut self,
 		child_storage_key: &[u8],
 		child_definition: &[u8],
 		child_type: u32,
@@ -313,6 +313,25 @@ pub trait Storage {
 	}
 }
 
+/// Interface for managing transaction within the runtime.
+#[runtime_interface]
+pub trait Transaction {
+	/// Start a new transaction.
+	fn start_transaction(&mut self) {
+		self.storage_start_transaction();
+	}
+
+	/// Discard a transactional layer.
+	fn discard_transaction(&mut self) {
+		self.storage_discard_transaction();
+	}
+
+	/// Commit a transactional layer.
+	fn commit_transaction(&mut self) {
+		self.storage_commit_transaction();
+	}
+}
+
 /// Interface that provides trie related functionality.
 #[runtime_interface]
 pub trait Trie {
@@ -908,6 +927,7 @@ pub type TestExternalities = sp_state_machine::TestExternalities<sp_core::Blake2
 #[cfg(feature = "std")]
 pub type SubstrateHostFunctions = (
 	storage::HostFunctions,
+	transaction::HostFunctions,
 	misc::HostFunctions,
 	offchain::HostFunctions,
 	crypto::HostFunctions,

primitives/state-machine/Cargo.toml

@@ -11,6 +11,7 @@ parking_lot = "0.9.0"
 hash-db = "0.15.2"
 trie-db = "0.19.2"
 trie-root = "0.15.2"
+smallvec = "0.6"
 sp-trie = { version = "2.0.0", path = "../trie" }
 sp-core = { version = "2.0.0", path = "../core" }
 sp-panic-handler = { version = "2.0.0", path = "../panic-handler" }
@@ -21,6 +22,13 @@ sp-externalities = { version = "0.8.0", path = "../externalities" }
 
 [dev-dependencies]
 hex-literal = "0.2.1"
+criterion = "0.2"
+rand = { version = "0.7.1", features = ["small_rng"] }
+
+[[bench]]
+name = "bench"
+harness = false
 
 [features]
 default = []
+test-helpers = []